1: 93 percent / NaHCO3 / diphenyl ether / 0.5 h / Heating 2: 100 percent / MeOH; HCl View Scheme

1: 86 percent / NaHCO3 / diphenyl ether / 0.5 h / 260 °C 2: Et3N, DMAP / CH2Cl2 / 0 °C 3: Bu3SnH, AIBN / benzene / 80 °C 4: 30percent H2O2, KHCO3 / methanol; tetrahydrofuran / Heating 5: 100 percent / imidazole / dimethylformamide 6: iPrEtN, DMAP / CH2Cl2 7: TBAF / tetrahydrofuran 8: SO3*Py, Et3N / dimethylsulfoxide 9: NaClO2, NaH2PO4*2H2O, 2-methyl-2-butene / 2-methyl-propan-2-ol; H2O 10: CH2Cl2 11: 98 percent / AcCl / methanol View Scheme

sodium hydrogencarbonate in diphenylether retro Diels-Alder reaction; 0.5 h; Heating;

1: 86 percent / NaHCO3 / diphenyl ether / 0.5 h / 260 °C 2: Et3N, DMAP / CH2Cl2 / 0 °C 3: Bu3SnH, AIBN / benzene / 80 °C 4: 30percent H2O2, KHCO3 / methanol; tetrahydrofuran / Heating 5: 100 percent / imidazole / dimethylformamide 6: iPrEtN, DMAP / CH2Cl2 7: TBAF / tetrahydrofuran 8: SO3*Py, Et3N / dimethylsulfoxide 9: NaClO2, NaH2PO4*2H2O, 2-methyl-2-butene / 2-methyl-propan-2-ol; H2O 10: CH2Cl2 11: 98 percent / AcCl / methanol 12: 96 percent / aq. 1 M NaOH / tetrahydrofuran; H2O View Scheme